A spot welding system includes a spot welding gun, a robot, and a tip dresser that polishes a face of electrode. The tip dresser includes a blade that cuts the face of the electrode and a blade driving motor that rotates the blade. A dresser control section of a control device detects torque of the blade driving motor. When the torque of the blade driving motor exceeds a predetermined torque upper limit value, the dresser control section carries out speed reduction control that reduces the rotation speed of the blade driving motor.

A cap dispenser for a welding gun includes a sleeve that slidably receives a drawer that is configured to house a column of weld caps. The cap dispenser also includes a spring that cooperates with a slide block that is arranged in the drawer. The spring urges the slide block toward an aperture in the drawer that is configured to receive a welding gun electrode.

A cap extractor for a welding gun includes a housing, a pair of springs, and first and second arms that are arranged between the springs. Each of the first and second arms have teeth that are configured to engage a welding cap. The first and second arms are configured to move relative to the housing in first and second directions that are transverse to one another by deflecting the springs.

A vehicle composite member to be joined at a perimeter section to a ferrous vehicle body member is provided. The vehicle composite member includes a lightweight panel that is formed of a lightweight material having a lighter specific weight than iron, and a ferrous perimeter member that has been integrated with the lightweight panel. The perimeter section is configured by the ferrous perimeter member.

A welding gun and a welding method with which it is possible to reduce the wait time for loading a component and to decrease tact time. The welding gun is a welding gun for resistance-welding components to a workpiece successively, and comprises a first holding portion and a second holding portion for holding a component. The first holding portion and the second holding portion are each switchable to an abutment-enabling position for causing a component to abut against a workpiece, or to a loading-enabling position for loading the component. The first holding portion and the second holding portion are switchable such that when the first holding portion is in the abutment-enabling position, the second holding portion is in the loading-enabling position, and when the second holding portion is in the abutment-enabling position, the first holding portion is in the loading-enabling position.

A cap dispenser for a welding gun includes a sleeve that slidably receives a drawer that is configured to house a column of weld caps. The cap dispenser also includes a spring that cooperates with a slide block that is arranged in the drawer. The spring urges the slide block toward an aperture in the drawer that is configured to receive a welding gun electrode.

A resistance welder, which includes a clamp for supporting a detachable arm, the arm being constituted by a fixed part supporting a fixed electrode and a rotationally mobile part supporting a mobile electrode. The electrodes are intended to be crossed by an electrical current. The mobile arm of the clamp is pushed in its rotational motion by a thruster so that the extremities of the electrodes approach each other and grip the elements to be welded. The clamp further includes a shift measurement sensor, the value measured by this sensor being proportional to the distance between the extremities of the electrodes. It is thus easy to measure the distance between the electrodes and the measurement made on the piston can be used for other types of arms.

A device for twisting-off and stripping an electrode cap from an electrode cap receptacle of an end of a welding gun of a welding robot, the device comprising a cap twisting-off unit and further comprising a stripping device. The stripping device is arranged along an insertion path for an electrode cap receptacle with an electrode cap as seen in front of the cap twisting-off unit and along a discharge path for an electrode cap receptacle without or with electrode cap as seen from behind the cap twisting-off unit. The stripping device can be for use in combination with the cap twisting-off unit.

Provided is a spot welding machine able to perform spot welding in which the desired nugget size is formed while suppressing spatter even if the strengths or thicknesses of the metal sheets change, the machine comprising: a pair of electrode tips, a pair of pressing members arranged around the tips, a first power supply, first and second drive mechanisms, and a pressing force control part, wherein the tips and the pressing members are respectively arranged facing each other so as to be able to sandwich a set of sheets between them, the first drive mechanisms give pressing forces pressing the tips against the sheets, the second drive mechanisms give pressing forces pressing the pressing members against the sheets, and the control part independently controls the pressing forces given by the first and second drive mechanisms.

A method for welding multiple workpieces together includes applying a force to the multiple workpieces, generating ultrasonic vibration, transferring the ultrasonic vibration to the multiple workpieces to breakdown an oxide layer, generating an electric current, transmitting the electric current to heat up the workpieces, and synchronizing the ultrasonic and resistance heating operations. A welding system includes an ultrasonic vibration unit that generates an ultrasonic vibration and transfers the ultrasonic vibration to multiple workpieces to breakdown an oxide layer, a resistance heating unit that generates an electric current and transmits the electric current to heat up the workpieces, a workpiece mount that includes electrodes configured to receive the generated current and/or clamp the multiple workpieces during a welding process, and a controller configured to synchronize an operation of the ultrasonic vibration unit and an operation of a resistance heating unit.